Paraffin tool



E. HEBERT PARAFFIN TOOL 3 Sheets-Sheet 1 Filed June 29, 1959 'urli/443414154!!Ulnlnfllflnlnfnvnnaa INVENTOR Ew//v Hfeaer' BY W kid-47 ATTORNEY E. HEBERT PARAFFIN TOOL `fan. l5, 1963 5 Sheets-Sheet 2 Filed June 29, 1959 INVENTOR En w//v HEBERT ATTORNY E. HEBERT PARAFFIN TOOL Jan. 15, 1963 3 Sheets-Sheet I5 Filed June 29, 1959 INVENTOR EDw//v /skr BY n-f4 L? ORNEY 3,073,391 ARAFFIN TOOL Edwin Hebert, Breaux Bridge, La., assigner to Southern rResearch and Sales Corporation, a lcorporation of Louisiana Y Filed June 29, 1959, Ser. No. 823,549

9 Claims. (Cl. 16d-172) The present invention pertains to an apparatus for scraping, cutting, and removing sediments from the inner wallsV of a substantially vertical ud conduit.

More particularly, the invention pertains to an appaf ratus for cleaning accumulations of paraifin from the casing of oil wel1s,'aud of sludge and bacterial growth from water, gas, sewer andvother pipes.

To identify the apparatus further, it is suitable for insertion into substantially vertical pipelines, such as a well for actuation therein from above ground, and it employs cleaning means such as a knife, a scraping cutter, a brush, or combinations thereof mounted on a weighted central member for propagation of the cleaning means axially relative to the well casing.

Y In uid conduits ofthe type described, sediments deposit on their inner walls, of varying consistencies and states of solidifications, usually lnot evenly throughout the line, but sporadically, occurring only at certain levels, for varying lengths, narrowing the bore of the conduit, and thus decreasing its output. -The irregular distributions'of the sediments contribute to the difficulties of cleaning the lines.

The devices of this type employed by prior art for cleaning oil wells by mechanical means, teach the lowering of a heavy tool into the well. The tool is suspended by means of a steel wire. Attached to the bottom end of the tool below a weighted portion thereof is a knife the purpose ofL which is toV `dislodge the paraffin, the cutting or scraping action of the knife resulting from the downward motion of the tool by gravity. When the parain is hard, or present `in large quantity, and stops the descent of the tool, further descent is obtained by means of a hammering or jarring action of the tool. This action is accomplished by the operator pulling on the Wire, thereby raising the. weight, then releasing the wire, dropping the weightto thus strike out and 'restart the knife. i

As the paraffin is cut away from the pipe it has to Vflow past the bulky weight.k In so doing, it sticks to the tool and impedes the flow of 4oil past the tool.y If

this impediment to flow becomes great enough, the pressure of the oil below the tool may actually blow the tool up the well, causing a great deal of danger and also difficulty as a result of tangled wire. Since the paraffin is cut away from the pipe below the tool, the'descent of the tool tends to push this dislodged parafin ahead get jammed ina pinched portion of the pipe. In addiction, 'since the ring-knife is concentric with the pipe and when stuck. Every prior vdevice known increases obstaclesl to the ilowv of the fluid during the cleaning process.

'.'The primary object of the invention is to obviate these deficiencies of the prior art apparatus for scraping, cutting,

brushing, and removing sediments from wells and similar lfluid conduits. v y j Another object of the invention is to provide adevice of it; thusimpeding the progress of they tool. The rigid ring-shaped knives of the prior art, being inflexible, `often v l 3,073,391 PatentedVJan;y 15, k1963 of this kind which eliminates the downward pushing into the well of the scraped o sediments.

Another object of the kinvention is to position the weighted bulk of the tool below the cutting knife or other cleaning means.

- Another object is to vprovideua tool, the bulk of which Another object of the invention is to provide a tool during operation. u

Another object of thelinvention is to provide a tool which permits a lcontinuous and'uninterrupted flow of fluid through it while in operation.

Another object is to provide atool design which presents a minimum of obstructions to which paratiin or which utilizes the ow of the fluid to clean the knife other sediments can adhere during passage through the` conduit.

Another object ofthe invention isl to provide avrknife which presents agminimum obstruction togthe free flow of sediment once removed, v

Another object of the invention is to provide a knife which will require arninimum of repair and replacement per units of work accomplished. f Another object of the invention is to provide a 'knife which will not jam in pipe joints, pipe imperfections, or in hard sediments. j

Another object of the invention is to provide a tool of minimum overall weight, light enough for `convenient handling yet of highest efficiency. f

Another objectief the invention is to provide a com-y -tbination suspension cutter and knife assemblywhich per- Ithe knife atA the extreme upper makeup, weigh, diameter, and length can be easily adaptl ed to the particular need. Y

Yet another object of the invention is to provide a tool of the kind described combining advantageously a central rod, weight, cutter, and suspension means .in an assembly designed specifically for optimum cooperation and improved joint performance.

Other objects and many of therattendant advantages of thisv invention will be readily appreciated as they become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate `like or correspondingparts throughout the ligures thereof,y and wherein; f

FIGURE 1 is a cross-sectional view through la ,Wellcasing, with a portion shown broken off, with portions of the vthe yapparatus of the invention shown therein in side view, ,diagrammatically and in cross-section;

FIGURE'Z is a similar view of another embodiment of y the invention;

j FIGURE 3 is a cross-sectional view of a complementary partl of the bottom part of the device, common to the embodiments of FIGURES 1 and 2; j Y

, FIGURE 4A and 4B are views of cutters of the inven- 3 tion, common to the embodiments shown in FIGURES 1 and 2;

FIGURE 4C is a view of a brush which may be used alone or in assembly with the cleaning means of FIG- URES 4 or 5; v

FIGURES 5A and 5B are perspective views of an other embodiment of a cutter which may be employed with the embodiments of FIGURES 1 or 2;

FIGURE 6 is a cross-sectional view of a detail of the apparatus of FIGURE 2;

FIGURE 7A is a view of a helically-shaped cutter integral with a vertical vane attached to a sleeve-type collar or tube section;

FIGURE 7B is a view of a helically-shaped knife integral with a vertical vane with two separate collars; and

FIGURE 8 is a cross-sectional View of a combination of the knife-guide rod and rope socket which are interchangeable witha'ssemblies common to embodiments of FIGURES 1 and 2.

There is shown, in FIGURE y1, a vertical well casing 11, a knife-guide rod 12, suspended therein axially by means of wire or cable 13 by means such as a socket 14 with lock-nut 1S, or as shown and described with reference to FIGURE 8, by forming a knife-guide rod 12 as a fishing head 18a centrally bored at 4t)` to accommodate wire or cable 13 which is secured below the base of said knife-guide rod by means such as the ring or eyelet 47.

The wire is fed from above the well manually or by motor means, not shown, preferably over a pulley from a rotatable drum 17. These are conventional means and form no part of the present invention.

The upper end of the rope socket is provided with a flange 18, permitting engagement with an auxiliary lishing tool, not shown, should the wire 13 fail. The diameter of the flange is of minimum safe dimensions, to provide ample space between it and the inner Wall of the casing.

The central knife-guide rod 12, shown in FIGURE '1, is connected at its bottom end to an elongated weighted tube 19. The weighted tube, preferably made of lead, comprises an inner axial bore with bypass orifices 21. The tube has a radius proportioned to the radius of the well casing and to the rate of flow of the fluid within the well, as will be hereinafter discussed.

The weight-of the tube 19 is predetermined by the diameter and length of the tube and by the anticipated sediment and flow of fluid upward through the conduit. The outer surfaces of the`tube 19 are smooth. The tube member 19 is provided at its head portion with means to fixedly engage the bottom part of the central rod, permitting axial suspension of the weighted tube within the casing. Conventional means are utilized for this purpose, such as threading of the members and securing by lock-nuts 23 and 24. In a simple form, the rod 12 is threaded at its bottom, is screwed into the weighted tube which is internally threaded, simultaneously closing the central axial bore 20 at its top and a lock nut 24 secures the connection. A circumferential groove 25, FIG. 6, is provided in the upper end of tube 19, below projection 23 for engagement with a fishing tool (riot shown), should the rod 12 and the weighted section become separated. The diameter of the weighted tube is smaller than that of the casing as will be hereinafter discussed. The length of the weighted tube is predetermined by various factors of the entire assembly, such as its radius and weight.

The tube is tapered at its bottom end. In FIGURE 3, a tip 26 is shown axially bored at 27, threadedV at its top at 28, having preferably a top diameter the same as and axially aligned withthe bottom of the weighted tube 19. The tip is tapered as shown, and in accordance with the invention serves as the bottom end of the tube which has a corresponding thread 28 in its vlower end.

FIGURE 4A shows a cutter-blade or knife 29, attached at` its upperr end to asleeve 30 and at its other end 'to collar 31 which is slidably mounted on central rod 12. The cuttenblade is shown as having a helical shape mounted axially over and extending about the central rod, the diameter of the helix being just slightly less than that of the casing.

In another embodiment of the invention, however, the cutter-blade is made of spring steel of a predetermined length and resiliency, related to the weight 19.

In FIGURE 4A, collar 31 is mounted -on the central rod 12 in position adjustably fixed by a set screw 31a, while the upper Vcollar Iii)y is movable. A stop may be provided by a set screw 30a fixed in rod 12. *During cleaning operations, the lateral dimensions of the cutterblade, that is, the effective radius of the helix formed thereby, will change automatically. In response to a considerable increase in the density or hardness of the sediment in the pipe an increased pressure will result on the cutters edges. The top collar 30 of the cutter, when freely movable, will distance itself automatically from the bottom collar 31. The helix defined by the resilient blade will thus elongate its lateral diameter will decrease and the angle of its cutting edge relative tot the wall will decrease. Thus, the cutters radial sphere of cutting influence will be reduced to an adequate ratio and will increase aut-o-maticallyy on reciprocation after a layer of the sediment has been sliced oft", or after the deposit accumulation in the following stages of its progress decreases. By these means a definite variable optimum relationship be tween the distance lof the cutters top and bottom sleeves, and'its natural slope are obtained relative tothe radius of the pipe, limited only by the predetermined resiliency of the cutter blade. Since the complexity of the factors involved makes precalculations very difficult, the` adinstability of the sliding means 30a and 31a, here described, permits easy and quick experimentation of the optimum positions of the collar 31 relative to the stop of the upper sleeve 30. Cutters of different resiliency may be easily and quickly substituted. In the spirit of the invention, the top sleeve 30 may be fixed to the central `rod 12, with collar 31 fixed or slidable, depending on the particular requirement in the field, such as the degree of hardness of the deposit to be removed.

In Vanother embodiment of the invention the cutter blade, instead of being a helically wound cutter blade, is a spiral cutter blade, FIGURES 5A and 5B, having a bottom -turn of the same diameter as that of the weighted tube, the diameters of the subsequent turns increasing in sequence up to a maximum diameter almost equal to the diameter of the casing, may be employed with or without the differently sliding sleeve arrangement ofthe two collars described with reference to FIGURE 4A. The helical or spiral cutter blades of FIGURES 4A and 5A are provided preferably with conventional tapered knife edges` on their upper and lower peripheries, as shown at 29aV and 29b, in FIGURE 8.

While one full loop to the cutter bar is necessary, a

plurality of loops, depending on the selected weight,.

velocity, and momentum factors, are desirable.

The axial bore through tube 19 withV the branches or by-passes 21 at its head and with a circumferential spacing between the outer wall of the weighted tube and the inner wall of the casing, as shown in FIGURE 1, are calculated to provide for a flow of the fluid upwards through the well without interruption during the cleaning process; In fact, the cleaning process advantageously utilizes any such existing flow to transport the sediments, separated from the wall of the casing by thercutter blade, upwards and out of the well. -To aid this function of the weighted tube, the diameters of the inner bore 20, of the branches or bypass orifices 21 thereof, and of the weighted section 19, are scaled carefully relative to the diameter of the casing and the expected thickness of sedimentation to produce a jet-type flow through and around Vthe weighted tube upwards. The optimum weight of the weighted tube is related to theA resiliency and to the scraping surface of the cutter blade, to the expected amount of sedimentation on the wall of the casing, to the length of the tubeand't'o the velocity of impact. The means to control the resiliency and angle of cuttingof the knife are shown as set screws thesedimensions. Therefore, in a preferred embodiment oftheV inventionysuch `as shown in-FIGURE 11, means are provided to vary the weight of the,y tube membery 19.

The tapered bottomltip, being easily'removable, offers" the opportunity of interposing additional tube sections 22, screwed to thebottomof the weighted tube as lits `continuations, prior. to the' attachment of theV tapered bottom? tip, lto add extra weight if necessary.. Suchl continuation 1 sections also` may' have aldiameter greater or smaller Vmatically decreased, allowing it to turn closer to the vertical past'any minor obstruction.

`The ,sleeve mounting of the knifev permits a certain amount of repeated jarring action. If the knife should encounter paraiiin of ysuch hardness that the Weight of the tool is unable to pull it through, the weighted part of the toolcan be raised repeatedly the distance of the knife- Vguide rod without disturbing the position of the knife.

When the weighted ypart is thendropped, 'it imparts a thrust to the,V knife when the upper stop of the knife'guide rod strikes the knife sleeve. l

1n FIGUREz the embodiment of theirs/entren' shown in FIGURE l is shown, .slightly changed.

than that of the topf-weighted tube 19 to aid in the formalk tion of van optimum jet flow through theVV axial bore by decreasing the spacing between .casing and tube. j

During the well cleaning -operation the apparatus is lowered linto the.- casing from drum 17, with the cutterblade following the weightedtube by gravity. When the cutter-blade engages a sediment which it cannot slice'oif the Wall byv its own weight Vand momentum, the weighted Y tubecontinues its downward progressy unimpeded, while `the cutter-blade is still stuckor retarded inv progress in the sediment, L If the cutter `arrangement includes the variableY distancing of thetwo sleeves, as described above with reference vto FIGURES 4A,*4B, 5A and 5B, the resiliency of the cutter-blade comes iirst into elect and may help the blade vto complete the cutting ofthe sediupper sleeve of the cutter barwith the weight and momentumof the weighted tube, and a=jarring impetus is imparted` walls is above the tool andis flushed upwards and out `of the-well by the Viiowing oil,"without'becoming-lodged tube, with its decreased diameter, permits it to'fslide readily through parafrin deposits, and also offers less opportunity for the parafn to stick to the tool. The bore through the center of the tool permits the continuousr low of oil throughthe tool, eventhough it may become lodged in a heavy layer of paraliin, thereby preventing a build-up of pressure'below the tool and averting the danger of oil through the hole in "the tool emerges just underv mentv and free itself;` If this does not suice, or the arl vrangement has not been included, the socket 14 hits the The" central rod 12 `is V'provided with an axial bore 4i).

The wire 13 is not attached to the topof the `central rod,

as in FIGURE 1,v but passes freely lthrough the bore 40v and connects witha supporting rodl`41, of a diameter larger than thebore of rod 12 and having an auxiliary weight 42 attached to its lower end. Weight 42 is axially suspended within'a thin walled tube .43 for reciprocation therein. Tube 43 has Vits upper portion provided with jet orifices 4S directed intothe casing around the central rod. The lower end of rod 12 is threaded at 46,` FIGURE 8, to engage the Ythreaded upper end of the bore vof tube 43 thereby. to rigidly unite these parts,` as clearly shown upon FIGURE 6, VThe bottom periphery of the upper portion 44 of the tube forms a stop to the upward movements of the weight 42. The cutter Lblade 29 is mounted on the central rod 12in the manner described with reference toFIGURE 1; This-arrangementzprovides for `a double jarring action ofthe cutter "blade, ifthe latter should be retarded or stopped in its progress. Upon being lowered in assembly linto the well, the cutter yblade proceeds irst by its own momentum. VIf the blade is retarded or stopped by the sedimentatiomthe weight 42 continues its own downward progress, ceases to support `by its upper part the upper portion 44 of the tube 43.' i Thus the tubel itself creates, by its own momentum, a first jarring action upon thecutter blade through socket 14. If the cutter blade does not respond to it by continuing its downward progress, the vweight 42, in its own travel through-the Varound the tool itself. The smooth surfaceof the weighted' Y tube 43, finally hits the bottom of thev tube 43, creating a second jarring impact of the socket 14 on the cutterV blade. g p

i .FIGURE 6` shows details of the means to connect tube 43 with the centralrod 12v and the wire 13 with the` weight 42.

, FIGURE 7A shows a form ofthe invention wherein Y .knifefguidefrod `12 has a tube section 30a attached to it. A

of having the tool blow up the well. In addition, the flow l neathlthe' knife'mandl keepsth'e'knife washed clean of Y parain which has been out loose. i

`Thecutter 29'preferablyhas its blade inclined downwardly and outwardlyrelative to the iuneryertical wall of the casing at an'acute angle up to 45 The lower turns of the helix or the spiral of the cutter may be crimped into small narrow folds simultaneously. This crimping breaks up the sliced olf sediments into small particles. The fo1- lowing turns of the cutter then easily scrape off the remainder of the sediment left on the wall. In the alternative, a plurality of radial iinsymnnng parallel to the axis, such as 33, shown in FIGURE 8, may beuse'd. t

The helical or spiral spring steel knife, by virtue oflits thin, small surface and of'its cutting angle Afrom vertical vane 33 is fixed to and outstandsradially from the tube section, and the ends of the blade 29 are secured to the respective ends of thisvane, with a full 360 turn about the rod. This construction is also shown upon FIGURE 8.

FIGURE 7B shows another form wherein rod 12 has a sleeve 30b and a collar 31b attached .to it, in axiallyspaced relation. Vane 32 is xed at its ends with the sleeve and collar, and blade 29 is, in turn, fixed at its ends to the respective ends of the vane.

Instead of a rope socket, with the knife-guide rod and cutting assembly attached below, shown in FIGURES 1 and 2, FIGURE 8 combines the functions of the rope socket and guide rod by providing a central bore 40 up to 45, 'produces agreatervslicing action and comminutation than a conventional knife disc with its cutting edge perpendicular to the axis of the pipe. This angle also prevents the knife -frombecoming lodged in the joints of the pipe. When the sedimentation causes an obstruction, suicient to extend the distance between sleeve 30 and collar 31, FIGURE 4A, the cutting angle is autodisclosure relates only to preferred vembodiments of the invention and that it is intended tocover all changes and modifications of the examples of the invention herein chosen for the purposes of the disclosure, which do not constitute' departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is: I

l. In an apparatus fore-cleaning well casings, a rod, a sleeve mounted onand about said rod at one end thereof for free axial sliding therealong, a collar mounted on and about said rod at the other end thereof for sliding adjustment therealong, a single blade comprising a length of resilient metal fixed at its ends with said collar and sleeve, respectively, and extending helically about said `rod for at least 360 thereabout, means operable to iix said collar to said rod in adjusted position therealong, and means iixed with said rod limiting movement of said sleeve tberealong in al direction away from said collar.

2. in .an apparatus for cleaning well casings and tubing, a rod, a sleeve rmounted onand about said rod for x limited sliding'therealong, a collar mounted on and about saidl rod-below said sleeve,-for adjustment therealong, a single blade of resilient metal strap having its ends secured to said sleeve and collar respectively, and extending helically about said rod for at least one full turnV thereabout, means releasably securing said collar to said rod in adjusted position therealong, means limiting upward movement of said sleeve on and along said rod, and a tubular weight having its upper end secured to the lower end of said rod in coaxial relation therewith.

3. In an apparatus as in claim A2, said rod having a diameter less than the external diameter of said tubular weight, the upper end of said tubular weight having lay-pass orifices whereby fluid may ow upwardly through said tubular weight, through said orifice, thence upwardly exteriorly about said rod. I

4. An apparatus for cleaning well casings and tubing comprising, ,a tubular rod, a sleeve mounted on and tting about said rod for axial` sliding therealong, abutment means lixed with said rod to limit upward sliding of said. sleeve with respect to said rod, a collar mounted on and fitting about said rod, below said sleeve, for axial adjustment therealong, a blade of elongated strip material having its ends lixed with said sleeve and said collar, respectively, a tubular weight lixed with kthelower end of said rod in coaxial relation therewith, there being a radial passageway through the Wall of said tubular weight at the top end thereof, and means for connecting Y a cable directly to engage and support said rod.

5. An apparatus as in claim 4, said tubular weight `comprising a plurality or" like sections detachably connected in fixed coaxial relation.

6. An apparatus for cleaning well casings and tubing, comprising a tubular rod, a sleeve mounted on and coaxially about said rod for translation therealong, first abutment means iixed with said rod to limit upward translation of said sleeve with respect to said rod, a coliar mounted on and coaxially about said rod, below said sleeve, for adjustment axially therealong, a blade disposed helically for at least 360 about said rod and having its ends fixed with said sleeve and said collar,

Zit)

with the lower end of said.rod in coaxial relation there-` with, there being passageways at. the upper end of said tubular weight through which tluid may flow upwardly and exteriorly about said rod, an auxiliary Weight loosely` slidable along said tubular weight, second abutment means fixed with respective ends of said tubular weight and determining respective upper and lower limiting posi-1.

tions of said annular weight with respect theretoand a supporting cable passing downwardly through said tubular rod and having its lower end lixed with said auxiliaryfV weight.

7. The apparatusas recited in claim 6, said sleeve and collar being vnormally spaced axially of said rod, means operable to fix said collar in adjusted position axially along said rod.

8. An apparatus for cleaning well casingsand tubing.' comprising, a tubular rod, having upper .and lower spaced` abutment means, a sleeve mountedcoaxially on and about said rod' for sliding therealong, a collar mountedV coaxially on and about said rod, below said sleeve, for

sliding therealong, a blade of strip spring steel having its` ends xed with said sleeve and collar, respectively, and

lextending helically about said rod, said sleeve and collarV having limited sliding movement on said rodbetween with, there being a passageway through said tubular weight at the upper end thereof through which fluid may fiow upwardly through said tubular weight, thence upwardly exteriorly about said rod, an auxiliary weight loosely r.mounted within saidtubular weight for limitedV movement axially thereof, anda supporting cable extending through said rod .andV having Vits end fixed with said auxiliary Weight.

9. In a device for cleaning tubing, a rod having a central longitudinal axis, a sleeve mounted on kand about said rod for guided translation along said axis, a collar mounted on anda-bout said rod for guided translation along said axis, acutter blade of resilient metal helically` disposed for at least one full turn about Vsaid axis and having its ends fixed, respectively, with said sleeve and said collar, abutment means fixed withV said rod and` 2,220,237 Hau rNo'v. 5, 2,415,729 Dana Feb. 1l, 1947 2,433,828 Gassen s Jan. 6,1948 2,588,554 Meynig Mar, 11, 1952itubular weight4 belowrsaid rod, means` 

9. IN A DEVICE FOR CLEANING TUBING, A ROD HAVING A CENTRAL LONGITUDINAL AXIS, A SLEEVE MOUNTED ON AND ABOUT SAID ROD FOR GUIDED TRANSLATION ALONG SAID AXIS, A COLLAR MOUNTED ON AND ABOUT SAID ROD FOR GUIDED TRANSLATION ALONG SAID AXIS, A CUTTER BLADE OF RESILIENT METAL HELICALLY DISPOSED FOR AT LEAST ONE FULL TURN ABOUT SAID AXIS AND HAVING ITS ENDS FIXED, RESPECTIVELY, WITH SAID SLEEVE AND SAID COLLAR, ABUTMENT MEANS FIXED WITH SAID ROD AND LIMITING AXIAL TRANSLATION FOR SAID SLEEVE IN THE DIRECTION AWAY FROM SAID COLLAR, AND MEANS OPERABLE TO FIX SAID COLLAR IN ANY SELECTED POSITION OF AXIAL ADJUSTMENT ALONG SAID ROD. 